Birds Like New Songs

Just as our love songs have changed over the years, scientists have shown that birds also move with the times by updating their songs. Young birds don’t like the oldies.

Elizabeth Derryberry, from Duke University North Carolina, had been studying the process by which birds develop local "accents". Ecologists have suspected for some time that birds have regional dialects and pay more attention to birds that speak their own local dialect than an out-of-towner's. But when Derryberry compared samples of male white-crowned sparrows' songs recorded in 1979 and a more recent recording, she discovered the more contemporary songs had a lower pitch and were also slower.

To find out if the birds would notice, she played the samples to male and female birds. It was immediately obvious that they preferred the more recent songs. Upon hearing the contemporary material the females solicited more copulations, and the males strutted about exhibiting territorial aggression.

These results show that, within a relatively short time, meaningful differences in song styles can emerge. This could have the effect of creating a barrier between isolated populations. Derryberry, who has written up the research in the journal Evolution, suggests that this could be one of the ways in which new songbird species emerge.

Taken from: The Naked Scientists: Science Radio & Science Podcasts